objective-c - 添加的按钮未显示在 UINavigationController 上

Question

我正在尝试动态创建一个 View Controller 并设置它的 View 和标题栏。事情似乎工作得很好。但是当我尝试设置导航栏的左键或右键时，它们就是不显示。我做错了什么？

   UIWebView *tempWebView = [[UIWebView alloc] initWithFrame:self.view.bounds];
    [tempWebView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"someurl"]]];

    UIViewController* tempViewController = [[UIViewController alloc]init];
    tempViewController.view = tempWebView;

    UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:tempViewController];

    UIBarButtonItem* closeButton = [[UIBarButtonItem alloc] initWithTitle:@"Close" style:UIBarButtonItemStyleBordered target:self action:nil];
    navigationController.navigationItem.leftBarButtonItem = closeButton;


    [self presentViewController:navigationController animated:YES completion:nil];

Answer 1

改变

navigationController.navigationItem.leftBarButtonItem = closeButton;

到

tempViewController.navigationItem.leftBarButtonItem = closeButton;

navigationItem 外观由导航 Controller 呈现的 View 处理，因此如果您将它设置在 UINavigationController 而不是 rootViewController ，它会在您第一次推送时被覆盖。